9x1 HDMI Multi-viewer switcher Seamless 4K HDMI 9 Screen Real Time Multi Viewer Screen Splitter 9 in 1 Out Switch Adapter 1x9

I purchased this multiviewer to show up to 9 computer desktops on a single large 4K TV. It did not perform to my expectations at all. I had already reviewed specs and knew my 4K TV would support full 3840x2160 resolution with 4:4:4 (per-pixel) chroma sampling. I've even run computers at full 4K resolution on the TV directly before with perfectly clear images. I was expecting this multiviewer would accept nine 1280x720 desktops and just tile them directly on the 4K TV, but the resulting output was not clear at all. After trying different settings on the computers, the multiviewer, and the TV, I was never able to find a configuration that led to clear desktop images. From what I can tell this device must be sampling at 4:2:2 or 4:2:0 which means it is skipping chroma data for some pixels, leading to fuzzy text and lines. This might work for general video content like cameras and moving video, but it is a no-go for data displays. Avoid if you are looking for sharp, clear computer images combined on one display.